Fatal error: Uncaught Error: Interface "MediaWiki\Hook\MediaWikiServicesHook" not found in /usr/www/otte/public/sphunt1/extensions/CategoryTree/includes/ConfigHookHandler.php:37 Stack trace: #0 {main} thrown in /usr/www/otte/public/sphunt1/extensions/CategoryTree/includes/ConfigHookHandler.php on line 37